Gearbox is deadly serious about Aliens. At the multiplayer hands-on event in Dallas in March, chief executive Randy Pitchford bounded on to the stage to say: "This is the sequel to Aliens that we've all been waiting for. It's the game I've been wanting to play since I saw that film so many years ago." Other members of the development team nodded their heads in tacit agreement.

Set for release this autumn, Colonial Marines is a first-person shooter set after the events of both James Cameron's movie and Alien 3. As such, it is a true canonical sequel, overseen and approved by 20th Century Fox. "There are a lot of people in that loop, a lot of executives," says writer Mikey Neumann. "But I think they like to leave the creative stuff to the creatives. It was a collaborative process though, we'd go to them with stuff and see how far we could push in certain directions. Ghost Newt solving mysteries was apparently totally not okay."

There have been meetings, too, with some of the luminaries of the Alien series. The team got time with Syd Mead, the famed concept artist who worked not just on Aliens but Bladerunner and Tron.

"He's an amazing guy, he invented the future," says Gearbox co-founder Brian Martel. "It was incredible to be able to go over to his house and check out all the original paintings and drawings." From Mead's blueprints, the art team was able to flesh out the Sulaco, adding detail that the movies only hinted at.

Martell also met with Sir Ridley Scott at his production company's office in LA. The director talked about the origins of the derelict craft in the original movie, and the possibility of it being a delivery mechanism for biological weapons. He also retrieved his original storyboards from Alien and talked through them.

"It was a weird fan moment," says Martel. "Just noticing things like the fact he used TV rather than movie-style storyboards because he'd come from a background directing commercials. And he hand drew them all."

Colonial Marines begins 17 weeks after the Sulaco was reported destroyed over Fury 161, the prison planet featured in Alien 3. The strange thing is that it's now in orbit over LV 426. We don't know why yet, but when the USS Sephora turns up to investigate, the crew are mighty jumpy about it all.

The campaign can be played alone or with a friend, via a drop-in/drop-out co-op function. As in the online multiplayer mode, it will be possible to upgrade weapons and also customise armour and guns, adding your own features and slogans, like the characters in Aliens.

The first thing fans may want to know is, why this timeframe? Why adopt David Fincher's somewhat controversial Alien 3 into the recipe?

"It made the most sense – there was a lot that happened in that movie," says Neumann. "A lot of it is kind of subtle, like Michael Bishop showing up at the end. That's really important, yet it's glossed over. Weyland-Yutani is paramount to our game. The main motivation, though, is being a Colonial Marine. Everyone wants to shoot a smart gun."

In the opening moments of our demo, which takes place near the beginning of the game, we find out that lead character Corporal Christopher Winter is part of a group of marines preparing to board the Sulaco from the Sephora, now connected to the apparent ghost ship via a long umbilical tunnel. A battalion of marines has already been in to investigate and, of course, all contact with them has been lost. Now it's time to find out what happened.

Aliens Colonial Marines

Naturally, what happened was slaughter. We arrive in the hanger of the Sulaco after a major battle between the marines and a bunch of alien soldiers. As CPR is being adminstered on a casualty in the background, we look around and immediately its obvious to fans that this is where the climatic battle between Ripley and the alien queen took place – you can even spot Bishop's legs in a pool of milky android blood on the floor.

Moving further into the ship, we pass a group of ejected cryotubes, hinting at whatever disaster caused the evacuation of Ripley, Hicks and Newt at the start of Alien 3. The mission is to find the craft's flight recorder, but on the way, we discover a soldier cocooned in an alien egg chamber. The poor guy doesn't know what's about to hit him, but he joins up with Winter.

The demo culminated in a shoot-out with a new kind of "stalker" alien – a sort of stealth monster that lurks in the shadows, scuttling over walls and ceilings to sneak up on you. The action is accompanied by James Horner's discordant action theme from the Aliens score, adding masses of tension. Marines shout stuff like "check those corners", harking back to the heavily militarised vernacular of Cameron's movie.

After setting sentry guns to guard his six, Winter escapes into the umbilical connector leading to the Sephora. But then his new companion starts convulsing, an alien busts out and in the confusion a thermal grenade is detonated, severing the tie between the two craft. The player, trapped in the now flailing tunnel, must complete an Uncharted-style quick-time sequence, clambering back up the passage avoiding debris, until you're back at the Sulaco. Trapped. With who knows how many aliens.

And the big question at this stage is, where did all these monsters come from? If only a small squad of marines boarded the Sulaco, how come the place is now teeming with xeno soldiers? Has the Gearbox team had to play fast and lose with the accepted lifecycle?

"We're doing a game that requires a lot of xenos, which obviously means we need a lot of hosts," says Neumann. "But we've had to stick to the canon that the audience understands - we can't make too much shit up.

"However, I've added my own section to the lifecycle cannon. It fills in a plot point we have on the gestation process. Now there's a little less vagueness in a certain area, based on some Weyland research. I was very proud of that."

A key element of the project has been capturing the atmosphere of horror and dread that typifies the Alien movies. A big part of that is the movement of the alien creatures – something only shown in glimpses by Scott and Cameron, but surely more exposed in an action video game.

Design director John Mulkey recognises this: "We spent a lot of time looking at how they move through the environment, how they go through ducts, and come down via air shafts – things that make it so they can get to you in frightening, unnerving ways. We don't want them running down the corridor at you, jazz hands waving! To be honest, we've had that iteration, but we're beyond that now!"

Neumann meanwhile sees the horror of the game in the way that a highly organised fighting machine very quickly unravels. "Aliens was about a small group of people watching everything spiral out of control, our game is about a large group – there are 400 people on the Sephora. It's about how can one tiny mistake endanger everyone, and how fast does that happen … and it happens fast."

What's clear is that the production design already shows a strong understanding of the Aliens aesthetic. The game features a deferred rendering engine, which draws the environment first and then lights the scene in real-time, allowing multiple dynamic light sources and authentic shadowing – and lights and shadows are of course pivotal devices in the movies.

Aliens Colonial Marines

"Over the course of this year as technologists start to talk about what next gen graphics are going to look like, you'll hear the phrase defered rendering alot," says Pitchford. "The lighting is natural and realistic instead of being pre-baked and cooked in before the processing takes place. It takes a lot of processing power and some high-end algorithms – and we're providing it in this generation."

There are quite obessive levels of authenticity here: art director Brian Cousins even studied the excessively grainy high speed film stock used by Cameron – Kodak 5294 – which the director apparently favoured and instisted on, even though it was being phased out at the time. It's an accurate approximation (at least on the beefy PCs running our demo), everything is dipped in a hazy blue-white light, the vast interior hulks reflect hazes of strip lighting from the more brightly lit sections. And when warning sirens go off, the revolving red bulbs send strobing arcs across every surface.

The team has had access to all the original audio files, so the pulse rifles, motion detector beeps, alien screams and alarm sounds are just right. The movie archives have been opened up, allowing access to set photos and props (Fox even loaned Sega the huge model of the alien queen used in Aliens to show off at its Colonial Marines press event. Insured for around £2m, it came with its own security guard).

The major question, and subject of much rumour and speculation, is over how the game may cover some of the ground being explored in Ridley Scott's forthcoming sci-fi movie – and alleged Alien "prequel" – Prometheus, particularly the origin of that derelict space craft. I put this to Martel: "It is definitely an area we're interested in, but we also knew [the movie] would be playing in that space. We'll get to it, but we won't explore it in the same way; we'll deal with our own take on it."

As for the future of Aliens games, Gearbox seems to have plans to stick around. "We're taking it one step at a time," says Martel. "But we think ahead and we'd like to make sure we leave something open so there can be a sequel.

"I'd love to see a long-running TV show, with the marines as the stars. I still think that's an area no one has explored – these guys, not just fighting bugs, but going off to war. I mean, what's happening in this universe where they're colonising planets that require a set of marines to go in and deal with problems. That part is really cool to me."

I'm not sure at this point whether we're talking about Martel's plans for a post-Aliens marine game, or if we really are picturing a TV series about characters like Hicks and Hudson. But this is all part of Gearbox's submergence into Alien lore. They really mean this.

I'm still conflicted. As authentic as the visuals are in places, as determined as the team is to craft something that respects the canon, we're 25 years on from Aliens – is there still that mass interest in the brand now? Especially since it has been mugged and disfigured by the risible Aliens v Predator flicks.

And can the bizarre psycho-sexual threat of the xenomorphs ever really be captured in a game? Does shooting dozens of these things deaden the impact? Gearbox certainly seems to be the right studio for this job, but is it a job that is already being done by the Dead Space series, which has successfully evolved the Aliens blueprint for an interactive age?

Anyone who loves the movies wants to see this done right though – and there is a lot to be intrigued by here. "This is a labour of love for us," said Pitchford in his demo day speech. "I've been stealing from the Alien films throughout my entire career."

So has everyone. Can this be the point at which the games industry starts giving back?

• Aliens Colonial Marines is due out on PC, PS3 and Xbox 360 in autumn 2012. For more information on the multiplayer mode, see our hands-on preview